Measurement Technologies
Measurement Technologies
(see Mentor Visual iQ Manual – Advantages of Measurement Types)
(see Mentor Visual iQ Manual – Advantages of Measurement Types)
3D Phase Measurement
3D Phase Measurement
Using patented structured-light technology, 3D Phase Measurement enables inspectors to locate, measure and analyze an
Using patented structured-light technology, 3D Phase Measurement enables inspectors to locate, measure and analyze an
indication using the same tip optic. The wide field of view and large depth of field allow for measuring with the same tips
indication using the same tip optic. The wide field of view and large depth of field allow for measuring with the same tips
used for inspecting, thus eliminating the extra steps required to back out, change the tip and then relocate the indication.
used for inspecting, thus eliminating the extra steps required to back out, change the tip and then relocate the indication.
In effect, 3D Phase Measurement provides accurate measurement "on-demand" while saving time and increasing overall
In effect, 3D Phase Measurement provides accurate measurement "on-demand" while saving time and increasing overall
inspection productivity. 3D Phase Measurement employs structured light patterns projected from the tip to create a 3D
inspection productivity. 3D Phase Measurement employs structured light patterns projected from the tip to create a 3D
surface scan of the viewing area and can measure all aspects of surface indications.
surface scan of the viewing area and can measure all aspects of surface indications.
Benefits:
Benefits:
• View and manipulate a 3D point cloud for detailed assessment of surface shape and measurement correctness
• View and manipulate a 3D point cloud for detailed assessment of surface shape and measurement correctness
• Full-screen viewing of measurement image for greater resolution
• Full-screen viewing of measurement image for greater resolution
• Navigate, inspect and measure without changing probes or tip optics
• Navigate, inspect and measure without changing probes or tip optics
• Available on 6.1 mm diameter probes
• Available on 6.1 mm diameter probes
3D Stereo Measurement
3D Stereo Measurement
Introduced in 2015, 3D Stereo Measurement is GE's newest video borescope measurement technology. 3D Stereo
Introduced in 2015, 3D Stereo Measurement is GE's newest video borescope measurement technology. 3D Stereo
Measurement utilizes the same optical tips as traditional Stereo Measurement but employs more advanced calibration and
Measurement utilizes the same optical tips as traditional Stereo Measurement but employs more advanced calibration and
processing algorithms to generate a full 3D point cloud representation of the target surface that can be viewed, manipulated,
processing algorithms to generate a full 3D point cloud representation of the target surface that can be viewed, manipulated,
and analyzed.
and analyzed.
Benefits:
Benefits:
• More accurate, repeatable measurement compared to traditional, outdated stereo or shadow measurement
• More accurate, repeatable measurement compared to traditional, outdated stereo or shadow measurement
• Provides better matching capabilities than Stereo Measurement on horizontal and repeating indications
• Provides better matching capabilities than Stereo Measurement on horizontal and repeating indications
• View the camera image and 3D point cloud side-by-side for highly efficient measurement analysis
• View the camera image and 3D point cloud side-by-side for highly efficient measurement analysis
• Measure effectively on shiny (or highly-reflective) surfaces which include detail
• Measure effectively on shiny (or highly-reflective) surfaces which include detail
• Measure on surfaces with some minor movement present
• Measure on surfaces with some minor movement present
• Available on 4.0, 6.1 and 8.4 mm probe diameters
• Available on 4.0, 6.1 and 8.4 mm probe diameters
Stereo Measurement
Stereo Measurement
Traditional stereo measurement, which, like 3D Stereo, utilizes a patented prism to obtain left and right stereo images from
Traditional stereo measurement, which, like 3D Stereo, utilizes a patented prism to obtain left and right stereo images from
slightly different perspectives. The matching of surface points in the left and right images at the cursor locations allows
slightly different perspectives. The matching of surface points in the left and right images at the cursor locations allows
3D coordinates and measurement results to be computed. This technology, available for more than a decade, is useful on
3D coordinates and measurement results to be computed. This technology, available for more than a decade, is useful on
systems with limited computing power but does not provide a 3D point cloud and therefore limits the inspector's ability to
systems with limited computing power but does not provide a 3D point cloud and therefore limits the inspector's ability to
assess measurement quality.
assess measurement quality.
Comparison Measurement
Comparison Measurement
A more traditional 2D measurement technology that uses a physical reference target placed by the manufacturer or
A more traditional 2D measurement technology that uses a physical reference target placed by the manufacturer or
inspector at the same tip to target distance as the indication.
inspector at the same tip to target distance as the indication.
PC Re-Measurement
PC Re-Measurement
Using software such as Inspection Manager to conduct post-inspection image measurement and analysis on a stored
Using software such as Inspection Manager to conduct post-inspection image measurement and analysis on a stored
image. Today re-measurement capabilities are also available on-device using the Mentor Visual iQ system or on PC.
image. Today re-measurement capabilities are also available on-device using the Mentor Visual iQ system or on PC.
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3D MEASUREMENT BEST PRACTICES: TECHNIQUES AND TIPS
3D MEASUREMENT BEST PRACTICES: TECHNIQUES AND TIPS
These best practices apply to both 3D Phase Measurement and 3D Stereo Measurement. Use this best practice
These best practices apply to both 3D Phase Measurement and 3D Stereo Measurement. Use this best practice
guide to provide the best results when setting up measurement with your VideoProbe. Additional guidelines for
guide to provide the best results when setting up measurement with your VideoProbe. Additional guidelines for
specific measurement types are listed on page 6.
specific measurement types are listed on page 6.
General Guidelines
General Guidelines
• Ensure the inspector is trained and qualified to perform
Ensure the inspector is trained and qualified to perform
•
measurement .
measurement.
Use in-house procedures or the selector tool on this page to
• Use in-house procedures or the selector tool on this page to
•
choose the appropriate measurement technology and type
choose the appropriate measurement technology and type
for your application.
for your application.
Ensure that your measurement tip and probe optics are
• Ensure that your measurement tip and probe optics are
•
clean and that the tip is securely attached. If using a stereo
clean and that the tip is securely attached. If using a stereo
tip, be sure to correctly identify the tip serial number when
tip, be sure to correctly identify the tip serial number when
first entering measurement . 3D Phase Measurement tips
first entering measurement. 3D Phase Measurement tips
are automatically recognized by the system.
are automatically recognized by the system.
• Verify that the system measures accurately with the
Verify that the system measures accurately with the
•
GE-supplied NIST traceable verification block before and
GE-supplied NIST traceable verification block before and
after performing measurements.
after performing measurements.
Position the tip as close as possible to the measurement
• Position the tip as close as possible to the measurement
•
area (low MTD value). Stereo and 3D Stereo require the
area (low MTD value). Stereo and 3D Stereo require the
image to be in focus, but with 3D Phase Measurement ,
image to be in focus, but with 3D Phase Measurement,
small depth measurements (< 0.010") are generally most
small depth measurements (< 0.010") are generally most
accurate when close enough for the image to be somewhat
accurate when close enough for the image to be somewhat
out of focus. Measuring from too far away is the most
out of focus. Measuring from too far away is the most
common cause of inaccurate measurements.
common cause of inaccurate measurements.
Pay attention to warnings displayed by the system during
• Pay attention to warnings displayed by the system during
•
measurement , which may signal improper setup or
measurement, which may signal improper setup or
inappropriate MTD for the measurement performed.
inappropriate MTD for the measurement performed.
• Check the measurement setup and cursor placement with
Check the measurement setup and cursor placement with
•
3D point cloud view. Many issues are difficult to recognize
3D point cloud view. Many issues are difficult to recognize
using the 2D image alone but are obvious in the 3D point
using the 2D image alone but are obvious in the 3D point
cloud.
cloud.
When performing small depth or depth profile
•
• When performing small depth or depth profile
measurements, use the 3D point cloud view with depth map
measurements, use the 3D point cloud view with depth map
enabled to verify that the indication clearly stands out from
enabled to verify that the indication clearly stands out from
the data noise. If not , capture another image from a closer
the data noise. If not, capture another image from a closer
distance or different orientation.
distance or different orientation.
• When measuring the depth of a feature such as a pit
When measuring the depth of a feature such as a pit
•
or dent , use the point cloud view to verify that you are
or dent, use the point cloud view to verify that you are
measuring at its deepest point and that the measurement
measuring at its deepest point and that the measurement
reference plane is accurately aligned with the reference
reference plane is accurately aligned with the reference
surface.
surface.
With 3D Phase Measurement , reflections or shadowing
• With 3D Phase Measurement, reflections or shadowing
•
can create regions of lower-quality data, which are
can create regions of lower-quality data, which are
highlighted in yellow. Avoid measuring in these areas
highlighted in yellow. Avoid measuring in these areas
whenever possible, especially for depth or depth profile
whenever possible, especially for depth or depth profile
measurements. Performing another capture from a
measurements. Performing another capture from a
different orientation may eliminate the yellow regions.
different orientation may eliminate the yellow regions.
Areas where the system was unable to determine 3D
• Areas where the system was unable to determine 3D
•
coordinates are highlighted in red. Measurements cannot
coordinates are highlighted in red. Measurements cannot
be taken in these red areas.
be taken in these red areas.
Choose the Right
Choose the Right
3D Measurement Technology
3D Measurement Technology
Is a 4 mm or 8.4 mm probe required?
Is a 4 mm or 8.4 mm probe required?
3D Stereo
3D Stereo
YES
YES
NO
NO
Are you measuring on highly-reflective, oily, or
Are you measuring on highly-reflective, oily, or
wet surfaces?
wet surfaces?
3D Stereo
3D Stereo
YES
YES
NO
NO
Is a side-view tip required?
Is a side-view tip required?
3D Phase Measurement
3D Phase Measurement
NO
NO
YES
YES
Do the viewing optics need to be very close
Do the viewing optics need to be very close
to the end of the side-view tip to see into the
to the end of the side-view tip to see into the
inspection area due to mechanical obstructions?
inspection area due to mechanical obstructions?
3D Phase Measurement
3D Phase Measurement
NO
NO
3D Stereo
3D Stereo
YES
YES
11 mm
3 mm
7.2 mm
2.7 mm
3D Stereo Side View
3D Phase Side View
3D Stereo Side View
3D Phase Side View
• For best data quality, keep the probe as still as possible
For best data quality, keep the probe as still as possible
•
during image capture. This is particularly important with
during image capture. This is particularly important with
3D Phase Measurement due to the large number of images
3D Phase Measurement due to the large number of images
captured.
captured.
With 3D Stereo, adjust image brightness and viewing
• With 3D Stereo, adjust image brightness and viewing
•
orientation to minimize glare in the area of interest prior to
orientation to minimize glare in the area of interest prior to
capturing a measurement image.
capturing a measurement image.
Straight lines or edges on viewed objects often appear
• Straight lines or edges on viewed objects often appear
•
curved in the 2D image due to the viewing perspective and
curved in the 2D image due to the viewing perspective and
optical distortion. As all measurements are performed in
optical distortion. As all measurements are performed in
3D, the straight 3D measurement lines are drawn on the 2D
3D, the straight 3D measurement lines are drawn on the 2D
image as they would be seen by the camera, which is often
image as they would be seen by the camera, which is often
curved. This helps with alignment to straight edges and
curved. This helps with alignment to straight edges and
more accurately indicates measurement location.
more accurately indicates measurement location.
VideoProbe 3D Measurement Handbook
VideoProbe 3D Measurement Handbook |
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